Keywords: silver nanoparticles, green synthesis, thermal decomposition, modified Tollens process, colloids, antibacterial effect
Novel silver nanoparticles: synthesis, properties and applications
In this paper, we present versatile and effective techniques to synthesise silver nanoparticles (Ag-NPs)-based compounds such as colloidal silver nanoparticles (CSNPs) and silver nanoparticles powders (SNPPs). The CSNPs stabilised by a surfactant oleic acid were produced for the first time through the reduction of [Ag(NH3)2]
(aq)complex by glucose with UV irradiation treatment, while the SNPPs were formed by thermal decomposition of silver-oleate complex at 330°C for 1 h. The CNPPs and CSNPs with average diameters (~9–10 nm) and highly stableaqueous dispersions were obtained. Noticeably, these synthesised Ag-NPs exhibited an excellent antibacterial activity against gram-negative Escherichia coli (ATCC 43888-O157:k-:H7) and methicillin-resistant gram-positive Staphylococcus aureus (ATCC 43300) bacteria. The electron microscopic technique provided deeper insights on the interaction and bactericidal mechanism of the Ag-NPs. Potential applications of the synthesised CSNPs and SNPPs for antibacterial – masterbatchs, acrylic emulsion paint as well as coating layer on cotton textiles were demonstrated.